I would stay away from HIGH PRESSURE water.
I've used diluted Simple Green for years and it has a tendancy to "hang on" to some kinds of metal for some reason. Even when you think you've rinsed the heck out of something it'll still keep foaming a bit, or you'll smell baking Simple Green the next time you run the car.
IMO, you want to use lots of LOW PRESSURE water for rinsing. Something like a "watering can" style attachment for your garden hose. Definitely avoid pressure/power washers as they'll drive water into water proof connectors, bearings etc... If you've done the cleaning properly, you won't need high pressure rinse as you're just rinsing the detergent and suspended/emulsified goo away with it. Don't let the detergent mix dry between application and rinsing.
Other detergents may not need as much rinsing, but I have continually altered my process to now use what seems to be a rediculous amount of rinse water to make sure I don't smell SG or see any more sudsing. I don't go crazy on the alternator, and I'd usually stay away from the distributor on cars that have them, but I haven't covered anything for years and never have an issue.
Fairly recently I've gone away from a trigger sprayer with SG dilution to using a hose-end sprayer meant for pesticide. Fill it with SG concentrate, set a mix ratio, and spray down the engine compartment. You can actually use less SG concentrate but get much better results. It also works great getting the salt and other [censored] off of the bottom of the car where a trigger sprayer would be a pain.
This has been working well for me for years on Japanese and German cars.